Relief-release pumps

ABSTRACT

A chemical feed pump which includes a pump head having an inlet check valve, a discharge check valve, a return check valve, a relief-release means, a pumping chamber, and a connecting passageway. The relief-release means includes a plunger member having a seal insert member offixed to its face and held in closing relationship to the connecting passageway through the action of a spring. The spring is mechanically held toward the pump head by a cap which has a set of inclined planes on its outward surface. A control knob is attached to the outward end of the plunger. The knob has a set of inclined planes facing the planes on the cap such that by rotating the knob the inclined planes will cause the spring to be compressed as they pull the plunger with its affixed seal insert away from the connecting passageway. When the plunger with the affixed seal insert is moved away from the connecting passageway, the pumping chamber is in fluid communication with the return check valve.

United States Patent [191 Pfleger RELIEF-RELEASE PUMPS [75] Inventor: Robert K. Pfleger, Miami,Fla

[73] Assignee: Ecodyne Corporation, Chicago, 111.

[22] Filed: June 13, 1973 [21 I Appl; No.: 369,699

4/1954 Wooley 417/308 X Primary ExaminerCarlton R. Croyle Assistant Examiner-Richard Sher Attorney, Agent, or Firm-Joel E. Siegel 111] 3,819,303 June 25, 1974 [57] ABSTRACT A chemical feed pump which includes a pump head having an inlet check valve, a discharge check valve, a

' return check valve, a relief-release means, a pumping chamber, and a connecting passageway. The reliefrelease means includes a plunger member having a seal insert member offixed to its face and held in closing relationship to the connecting passageway through the action of a spring. The spring is mechanically held toward the pump head by a cap which has a set of inclined planes on its outward surface. A control knob is attached to the outward end of the plunger. The knob has a set of inclined planes facing the planes on the cap such that by rotating the knob the inclined planes will cause the spring to be compressed as they pull the plunger with its affixed seal insert away from the connecting passageway. When the plunger with the affixed seal insert is moved away from the connecting passageway, the pumping chamber is in fluid communication with the return check valve.

7 Claims, 2 Drawing Figures RELIEF-RELEASE PUMPS This invention relates to a chemical feed pump and more particularly to a self-contained chemical feed pump for pumping liquid chemicals from a chemical container into the system being fed.

The heretofore known practices of feeding chemicals by a pumping means haveleft many problems in the hands of the user. Most chemical feed pumps can be readily installed to handle hazardous chemicals, however, once in operation many problems frequently arise. Failure to refill the chemical container causes the pump to run dry and the residue chemical fouls the check valves. Normal precipitation can also foul the check valves. Continous chemical attack or errosion can destroy the check valve seals. A clogged injection the pump head. Normal maintenance is hazardous due to the nature of the chemicalsbeing fed. The use of accessory items to correct any of the above problems only increases the number of chemical connections and adds more check valves and seals which require maintenance. Previous attempts to solve these problems have included provision of a relief valve in the head, a

back pressure bleed off to atmosphere or a combined cal feed pump which allows priming of the pump head when pressure is present at the discharge check valve.

A further object is to provide a self-contained chemical feed pump which allows flushing the head of dangerous to handle chemicals when maintenance is required on parts of the pump head or the pumping means.

Still another object of the present invention is to prov vide a self-contained chemical feed pump which routes dangerous to handle chemicals back to a safe container when an overload occurs, during priming or when flushing.

A still further object is to provide a self-contained chemical feed pump which allows the checking of all the check valves for leakage without disconnecting the pump from the system being fed.

The chemical feed pump constructed in accordance with the present invention includes a pump head having an inlet check valve, a discharge check valve, a return check valve, a relief-release means, a pumping chamber, and a connecting passageway. The relief-release means includes a plunger member having a seal insert member affixed to its face and held in closing relationship to the connecting passageway through the action of a spring. The spring is mechanically held toward the pump head by a cap which has a set of inclined planes on its outward surface. A control knob is attached to the outward end of the plunger. The knob has'a set of inclined planes facing the planes on the cap such that by'rotating the knob the inclined planes will cause the spring to be compressed as they pull the plunger with its affixed seal insert away from the connecting passageway. When the plunger with the affixed seal insert is moved away from the connecting passageway, the pumping chamber is in fluid communication with the return check valve.

BRIEF DESCRIPTION OF THE'DRAWINGS Other objects and many of the attendant advantages of this invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, in which like reference numerals designate like parts throughout the figures thereof and wherein:

FIG. 1 is a vertical sectional view of a chemical feed pump constructed in accordance with the present invention; and

FIG. 2 is an enlarged elevational view of the control knob portion of the feed pump illustrated in FIG. 1.

DESCRIPTION OF A PREFERRED EMBODIMENT Referring to FIG. 1, a chemical feed pump 10 is illustrated in combination with a container 12 containing the liquid chemical to be pumped and a conduit 14 to receive the pumped liquid. Pump '10 includes a pump head 16 in which is formed a pumping chamber 17 having an inlet passageway 18 and a discharge passageway 19 formed integral therewith. Pumping chamber 17 may be used with any suitable pumping means such as a diaphragm, piston, gear, etc. The specific pumping means does not form an important part of the present invention and, therefore, will not be herein discussed in detail as it would be obvious to one skilled in the art to provide such a suitable pumping means in chamber 17.

Cavities 20 and 21 are formed in head 16 respectively in fluid communication with inlet passageway 18 and discharge passageway 19. Received respectively within cavities 20 and 21 in a suitable manner are check valves 22 and 23. Check valves 22 and 23 may be of any suitable construction and preferably are of the type disclosed in US. Pat. No. 3,565,100, assigned to the same assignee as the present invention. Inlet check valve 22 includes a valve member 25 which is biased by spring 26 towards a valve seat 27 to prevent the flow of liquid from pumping chamber 17 therethrough. Discharge check valve 23 includes a valve member 28 which is biased by spring 29 towards a valve seat 30 to prevent the flow of liquid back into pumping chamber 17. A connecting tube 32 is secured at one end to the outlet side of check valve 23 by a connector 33 and at its other end to a suitable injection nozzle 34 by a connector 35. Injection nozzle 34 is received by conduit 14 to deliver the pumped liquid thereinto. Injection nozzle 34 may be of any suitable construction and preferably is of the type disclosed in US. Pat. No. 3,282,513, assigned to the same assignee as the present invention. A connecting tube 36 is secured at one end to the inlet side of check valve 22 by a connector 37 and its other end extends down into container 12.

A connecting passageway 40 formed within head 16 includes a pair of connecting ports 42 and 44. Connecting port 42 has a first end 46 in fluid communication with discharge passageway 19 and a second end 47 in 3 fluid communication with a cavity 48 formed integral with head 16. Connecting port 44 has a first end 49 in fluid communication with cavity 48 and a second end 50 in fluid communication with a cavity 52 formed integral with head 16. Received within cavity 52 in a suitable manner is a return check valve 54 of similar construction as discharge check valve 23. Return check valve 54 is spring biased to prevent the flow of liquid through a connecting tube 56, secured at one end thereto by a suitable connector 58, back into the port. The other end of tube 56 extends down into container 12.

The heart of the present invention is the provision of a relief-release valve 60for selectively controlling the passage of liquid through the connecting passageway 40. Valve 60 includes a plunger member 62, having a seal insert 64 affixed to its face, extending into cavity 48 and held against the end 47 of port 42 in sealing relationship thereto through the action of a spring 66. The outward end of plunger member 62 is sealed by dynamic seals 68. Spring 66 is mechanically held to pump head 16 by a cap member 70 which is received within a cavity 73 formed in head 16. The outward surface of cap member 70 has a set of inclined planes 72 formed thereon, as best seen in FIG. 2. A control knob member 74 is attached to the outward end of plunger member 62. Knob 74 has a set of inclined planes 76 positioned in facing relationship to planes 72 of cap 70 such that i by rotating knob 74, the relative movement of inclined planes 72 and 76 cause spring 66 to be compressed as they pull plunger 62 with its affixed seal insert 64 away from the end 47 of port 42. A pressure in port 42 which is greater than that created by spring 66 also causes plunger 62 and seal 64 to be moved away from port 42. Whenever plunger 62 and seal 64 are moved away from end 47 of port 42 the ports 42 and 44 are in fluid communication with each other.

A description of the operation of pump which hereinbelow follows more clearly, emphasizes the purpose of the combination of structural elements which are present in pump 10. Under normal operating conditions the pumping means alternatively creates a suction and a pressure within pumping chamber 17. When suction is created it causes valve member to unseat from seat 27 to permit liquid from container 12 to rise in tube 36 and pass through check valve 22 into pumping chamber 17. When pressure is created it causes valve member 28 to unseat from seat 30 to permit liquid to pass through check valve 23 into tube 32 and then through injection nozzle 34 into conduit 14. This pumping process continues to pump liquid from container 12 into conduit 14 in this manner unless the pressure within port 42 is greater than that created by spring 66 so as to cause plunger 62 and seal 64 to move away from end 47 of port 42. This opens ports 42 and 44 to each other and causes liquid to pass through passageway 40 with sufficient pressure to unseat check valve 54 and thereby return the liquid to container 12 via tube 56. The relief-release valve 60 may be pre-set t relieve pressures at various settings by changing the compression of spring 66. After the problem causing the excess pressure has been corrected, the pump returns to normal operation. This mode of operation automatically protects the pump head and the pumping means from overload.

To prime pump 10 it is necessary to turn knob 74 so as to move plunger 62 and seat 64 away from end 47 of port 42 and thereby open ports 42 and 44 to each other. The action of the pumping means is then able to pump air from the head 16 and draw liquid from container 12 into pumping chamber 17 and then thru passageway 40 to be returned back into container 12. With the head now primed, the knob 74 is turned to move plunger 62 and seat 64 back into closing contact with end 47 of port 42 so as to return the pump to normal operation. This same procedure may be followed when the system is under pressure since discharge check valve 23 will hold off the pressure to head 16 when valve 60 is in its open position. To flush pump head 16 of dangerous to handle chemicals the same procedure as for priming is followed except the tube 56 and the tube 36 are removed from container 12 to discharge the remaining chemical in the lines and head into a disposable container. This same procedure may be used to sample the chemical being pumped by leaving tube 36 in container 12.

An important feature of the present invention permits the checking of all the head check valves without disassembly, handling the chemical solution or shutting down the system being fed. This is accomplished by removing the power from pumping means and then .turning knob 74 until plunger 62 and seal 64 are spaced away from end 47 or port 42. If discharge check valve 23 is leaking, liquid will move downward within port 44. If check valve 23 is not leaking, power is returned to the pumping means and tubes 36 and 56 are lifted from container 12. lfinlet check valve 22 is leaking, the fluid will move upward and then downward in tube 36. If return check valve 54 is leaking, liquid will move downward and then upward in tube 56. If both check valves 22 and 23 are not leaking, liquid will move upward into pumping chamber 17 and then downward I through passageway 40. From the foregoing it should be clearly appreciated that the present invention provides a unique chemical feed pump which protects the pump head and pumping means from overload, allows priming of the pump head when pressure is present at the discharge valve, allows flushing of the head of dangerous to handle chemicals, and allows checking all the check valves for leakage without disconnecting the pump or the system being fed.

Various modifications are contemplated and may obviously be resorted to by those skilled in the 'art without departing from the spririt and scope of the invention, as hereinafter defined by the appended claims, as only a preferred embodiment thereof has been disclosed.

What is claimed is:

l. A self contained chemical feed pump for pumping liquid chemicals from a chemical container into the system being fed, said pump comprising:

a. a pump head;

b. apumping chamber defined within said pump head having pumping means associated therewith;

c. an inlet passageway formed within said pump head in fluid communication with said pumping chamber and said chemical container;

d. an inlet check valve means associated with said inlet passageway for preventing reverse fluid flow back into said chemical container;

e. a discharge passageway formed within said head in fluid communication with said pumping chamber and said system being fed;

f. a discharge check valve means associated with said discharge passageway for preventing reverse fluid flow back into said pumping chamber;

g. a connecting passageway formed within said pump head having a first end in fluid communication with said discharge passageway and a second end in fluid communication with a return check valve means for preventing fluid flow through said connecting passageway into said discharge passageway; and

h. a relief-release means associated with an intermediate portion of said connecting passageway for preventing the flow of liquid through said connecting passageway unless the pressure within said connecting passageway exceeds a predetermined value.

. said relief-release means being selectively operable to permit the flow of liquid through said connecting passageways before the pressure within said connecting passageway exceeds said predetermined value.

2. The invention as defined in claim 1 wherein said relief-release means includes a plunger member having a first position blocking the flow of liquid through said connecting passageway and a second position permitting the flow of liquid-through said connecting passageway, said plunger member being biased towards said first position.

3. The invention as defined in claim 2 wherein spring means is provided to bias said plunger member towards said first position.

4. The invention as defined in claim 3 wherein control means is provided to selectively move said plunger member from said first position towards said second position against the bias of said spring means.

5. The invention as defined in claim 1 wherein said relief-release means includes a plunger member having a first end movable between a first position blocking the flow of liquid'through said connecting passageway and a second position permitting the flow of liquid through said passageway. said plunger member being biased by spring means towards said first position, and a control means associated with a second end of said plunger member for selectively moving said plunger member from said first position towards said second position against the bias of said spring means.

6. The invention as defined in claim 5 wherein said control means includes a control knob secured to said second end of said plunger member and cap member secured to said pump head, said control knob and said cap member having inclined planes associated therewith in a facing relationship toeach other such that by rotating said control knob, said inclined planes cause said plunger member to move between said first and second positions.

7. The invention as defined in claim 6 wherein said cap member holds said spring means toward said pump head. 

1. A self contained chemical feed pump for pumping liquid chemicals from a chemical container into the system being fed, said pump comprising: a. a pump head; b. a pumping chamber defined within said pump head having pumping means associated therewith; c. an inlet passageway formed within said pump head in fluid communication with said pumping chamber and said chemical container; d. an inlet check valve means associated with said inlet passageway for preventing reverse fluid flow back into said chemical container; e. a discharge passageway formed within said head in fluid communication with said pumping chamber and said system being fed; f. a discharge check valve means associated with said discharge passageway for preventing reverse fluid flow back into said pumping chamber; g. a connecting passageway formed within said pump head having a first end in fluid communication with said discharge passageway and a second end in fluid communication with a return check valve means for preventing fluid flow through said connecting passageway into said discharge passageway; and h. a relief-release means associated with an intermediate portion of said connecting passageway for preventing the flow of liquid through said connecting passageway unless the pressure within said connecting passageway exceeds a predetermined value. i. said relief-release means being selectively operable to permit the flow of liquid through said connecting passageways before the pressure within said connecting passageway exceeds said predetermined value.
 2. The invention as defined in claim 1 wherein said relief-release means includes a plunger member having a first position blocking the flow of liquid through said connecting passageway and a second position permitting the flow of liquid through said connecting passageway, said plunger member being biased towards said first position.
 3. The invention as defined in claim 2 wherein spring means is provided to bias said plunger member towards said first position.
 4. The invention as defined in claim 3 wHerein control means is provided to selectively move said plunger member from said first position towards said second position against the bias of said spring means.
 5. The invention as defined in claim 1 wherein said relief-release means includes a plunger member having a first end movable between a first position blocking the flow of liquid through said connecting passageway and a second position permitting the flow of liquid through said passageway, said plunger member being biased by spring means towards said first position, and a control means associated with a second end of said plunger member for selectively moving said plunger member from said first position towards said second position against the bias of said spring means.
 6. The invention as defined in claim 5 wherein said control means includes a control knob secured to said second end of said plunger member and cap member secured to said pump head, said control knob and said cap member having inclined planes associated therewith in a facing relationship to each other such that by rotating said control knob, said inclined planes cause said plunger member to move between said first and second positions.
 7. The invention as defined in claim 6 wherein said cap member holds said spring means toward said pump head. 